WO2016030928A1

WO2016030928A1 - Impeller for fluid pump

Info

Publication number: WO2016030928A1
Application number: PCT/JP2014/004421
Authority: WO
Inventors: 在雄石; 悟司長尾; 誠人大澤
Original assignee: 株式会社Tbk
Priority date: 2014-08-28
Filing date: 2014-08-28
Publication date: 2016-03-03
Also published as: US20170268526A1; JP6438961B2; JPWO2016030928A1

Abstract

This impeller (100) for a fluid pump comprises: a disk-shaped shroud (150) rotated and driven about a center axis; and a cover (110) comprising a truncated circular cone-shaped cover body (120) having a fluid suction opening (123) formed at the center thereof, the cover (110) also comprising a plurality of blades (130) provided around the center axis of the cover body (120). The impeller (100) is configured such that the cover (110) and the shroud (150) are joined by welding a weld contact portion (135) and a weld receiving portion (177) together in the direction of the center axis while the other end surface of the shroud (150) and the front end sections (131) of the blades (130) are located in parallel with each other.

Description

Fluid pump impeller

The present invention relates to an impeller used for a fluid pump such as a water pump.

2. Description of the Related Art Conventionally, centrifugal fluid pumps that pressurize fluid sucked from a suction port and feed it from a discharge port by rotating an impeller formed with a plurality of blades are widely known. In addition to the open impeller in which the disk portion is provided only at one end of the blade, the impeller includes a closed impeller in which the disk portion is provided at both ends so as to sandwich the blade from both sides (for example, (See Patent Document 1). The closed impeller can be said to have higher pump efficiency than the open impeller, because a closed space is formed in the impeller by both disk portions, thereby preventing a flow of fluid leaking out.

JP 2011-252481 A

However, because the closed impeller has a structure in which both ends of the blade are connected by a disk part due to its structure, for example, when it is integrally formed as an injection molded product, a so-called undercut part is generated when it is removed from the mold, making mass production difficult. Can be a factor. Therefore, in recent years, by forming one disk part and the other disk part formed with a plurality of blades separately, and joining one disk part and the other disk part via a plurality of blades Although a technique for forming an integrated closed impeller has been put into practical use, there is a problem that it is difficult to sufficiently secure the impeller joint strength.

The present invention has been made in view of such problems, and an object of the present invention is to provide an impeller for a fluid pump that can increase the bonding strength with a simple structure.

In order to solve the above-described problems, an impeller of a fluid pump according to the present invention includes a disc-shaped impeller body member that is driven to rotate about a central axis, and a frustoconical cover that has a fluid suction port formed in the center. A fluid pump comprising: a main body; and an impeller cover member having a plurality of blades provided around a central axis of the cover main body, wherein the impeller main body member and the impeller cover member are disposed to face each other in the central axis direction. The cover main body has an inclined portion that is inclined radially outward toward the impeller main body member side in the central axis direction, and the plurality of the cover main bodies on the side facing the impeller main body member in the inclined portion. The impeller body member has a welding contact portion on a tip portion facing the impeller body member in the central axis direction. The one end surface facing the impeller cover member, the other end surface disposed on the opposite side of the one end surface in the central axis direction, and the tip end of the blade being recessed at a position aligned with the blade on the one end surface A groove portion that receives the groove portion, and a welding receiving portion that is formed in the groove portion and can contact the welding contact portion, and the other end surface of the impeller body member and the tip end portion of the impeller cover member are The impeller body member and the impeller cover member are joined by welding the welding contact portion and the welding receiving portion in a central axis direction in a parallel positional relationship. Note that the entire tip of the blade need not be parallel to the other end surface of the impeller body member, and at least a part of the welding contact portion of the tip of the blade may be parallel to the other end surface of the impeller body member.

In the impeller of the fluid pump according to the present invention, the blade is connected to the tip portion, a first outer surface connected to the tip portion on the rear side in the rotation direction, and a second side connected to the tip portion on the front side in the rotation direction. An outer surface, and the groove portion includes a groove bottom portion facing the tip portion in the central axis direction, a first inner surface connected to the groove bottom portion on the rear side in the rotational direction and in contact with the first outer surface, and the groove bottom portion. And a second inner surface connected to the front side in the rotational direction and opposed to the first inner surface, and the welding contact portion is formed at a corner between the tip portion and the second outer surface of the blade, It is preferable that the welding receiving portion serving as an inclined surface is formed on the second inner surface of the groove portion. In this case, at least the ridge line of the corner of the welding contact portion is parallel to the other end surface of the impeller body member.

According to the impeller of the fluid pump according to the present invention, the other end surface side of the impeller body member and the ultrasonic horn are arranged in a state in which the blade tip of the impeller cover member and the other end surface of the cover body member are in a parallel positional relationship. The ultrasonic horn is configured so that the impeller cover member and the impeller body member are pressurized and vibrated as the contact surface of the impeller, and the weld contact portion of the impeller cover member and the weld receiving portion of the impeller body member are welded. The pressure surface of the blade and the welded part of the blade and impeller body member are parallel to each other. As a result, vibration transmission loss (energy loss during vibration transmission) is reduced, so that stable quality with high joint strength can be realized. It becomes possible. Therefore, even when an impeller (closed impeller) is manufactured by welding and joining an impeller cover member and an impeller body member, a simple structure increases the joint strength and improves pump performance without increasing costs. In addition, there is an effect that a complicated blade shape and development to a large capacity pump can be realized.

Further, according to the impeller of the fluid pump according to the present invention, the welded portion between the weld contact portion and the weld receiving portion is formed as a shear joint, while the first inner surface pushes the weld contact portion into the weld receiving portion. In addition to acting as a guide surface, the first outer surface and the first inner surface are in contact with each other even if the welding contact portion is subjected to the action of the inclined surface of the welding receiving portion and attempts to escape and move away in the separation direction (first inner surface side). For this reason, the escape movement of the welding contact portion in the separation direction is restricted. Therefore, on the rear side in the rotation direction of the blades, by positioning the first outer surface and the first inner surface in a sliding contact state, the positioning accuracy of the welding contact portion and the welding receiving portion at the time of welding can be improved, On the front side in the blade rotation direction, the welded portion between the weld contact portion and the weld receiving portion is formed as a shear joint, so that a large welding area can be secured, thereby further increasing the bonding strength between the impeller cover member and the impeller body member. In addition, it is possible to prevent the occurrence of defects such as voids by making it difficult to entrain air during welding.

It is a front view which shows the water pump provided with the impeller which concerns on this embodiment. It is sectional drawing which shows the said water pump. It is a block diagram which shows the circulation path of the cooling water by the said water pump. It is a perspective view which shows the impeller which concerns on this embodiment. (A) is a front view showing the impeller, and (b) is a cross-sectional view showing the impeller along an arrow AA. (A) is a front view which shows the cover of the said impeller, (b) is a rear view which shows the said cover. (A) is a cross-sectional view showing the cover along the arrow BB, and (b) is a cross-sectional view showing the blades of the cover along the arrow CC. (A) is a front view which shows the shroud of the said impeller, (b) is a front view which shows the long groove | channel of the said shroud. (A) is sectional drawing of the said shroud, (b) is sectional drawing which shows the said long groove | channel along arrow DD. It is sectional drawing for demonstrating the manufacturing method (welding method) of the said impeller. (A) is sectional drawing which shows the state which the welding contact part of the blade | wing and the welding receiving part of the long groove contact | abutted, (b) is sectional drawing which shows the state which the welding contact part of the blade | wing and the welding reception part of the long groove welded It is.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. A water pump (fluid pump) according to an embodiment of the present invention is disposed in a cooling water circulation path of an engine and forcibly circulates cooling water. First, an overall configuration of this water pump is shown in FIG. This will be described with reference to FIG.

[Configuration of water pump]
The water pump 1 is assembled using a pump base 10 provided in a cylinder block of the engine EG as a base. The pump base 10 is provided with a suction port 11 connected to the cooling water return flow path L2 and

discharge ports

12 and 13 connected to the cooling water discharge flow path L1 to the water jacket WG. , 12 and 13 are open to the surface side of the pump base 10, respectively.

The pump body 20 is detachably attached to the back side of the pump base 10 by a plurality of bolts 21, and a space surrounded by the pump base 10 and the pump body 20 forms a pump chamber 2. An O-ring 22 is interposed between the mating surfaces of the pump base 10 and the pump body 20 in order to ensure the sealing property of the pump chamber 2. The pump base 10 and the pump body 20 constitute a pump casing.

A pump pulley 40 is attached to the outer peripheral side of the pump body 20 via a drive shaft 30. A belt groove 41 is formed on the outer peripheral surface of the pump pulley 40 so as to span a drive belt DB connected to the crankshaft CS of the engine EG. The drive belt DB spanned over the belt groove 41 is used to drive the crankshaft CS. The rotational force is transmitted to the pump pulley 40, and the pump pulley 40 is rotationally driven.

The base end portion of the drive shaft 30 is attached to the pump body 20 by press-fitting. The drive shaft 30 penetrates through the opening 23 of the pump body 20 in a state where the pump pulley 40 and the rotation shaft of each other are aligned. It extends to the pump chamber 2. The drive shaft 30 is rotatably supported by the pump body 20 via a bearing 31 fitted to the pump body 20. An impeller 100 is concentrically attached to the tip of the drive shaft 30, and the impeller 100 is disposed in the pump chamber 2. The pulley 40, the drive shaft 30, and the impeller 100 can be integrally rotated coaxially. A gap between the opening 23 of the pump body 20 and the drive shaft 30 is sealed by a mechanical seal 24 for maintaining the hermeticity of the pump chamber 2.

As shown in FIG. 3, the pump pulley 40 of the water pump 1 is rotationally driven by a crankshaft CS of the engine EG via a drive belt DB. As a result, the drive shaft 30 connected integrally with the pump pulley 40 rotates together with the impeller 100. The cooling water in the return flow path L2 sucked into the suction port 11 with the rotation of the impeller 100 receives a centrifugal force due to the rotation of the impeller 100 in the pump chamber 2, and is discharged from the

discharge ports

12 and 13 to the discharge flow path L1. Is discharged. The cooling water discharged to the discharge flow path L1 is pumped to the water jacket WJ, cools the cylinder of the engine EG, etc., and then flows from the connection flow path CL to the radiator RD to be radiated. And it returns to the water pump 1 again from the return flow path L2, and is circulated. The connection flow path CL is provided with a switching valve SV that is operated by a thermostat, and when the temperature of the cooling water is higher than a predetermined set temperature, the cooling water flows to the radiator RD. When it is lower than the temperature, the cooling water is allowed to flow through the bypass passage BL. The bypass flow path BL communicates with the return flow path L2, and is directly sucked by the water pump 1 without passing through the radiator RD. In this way, the water pump 1 forcibly circulates the cooling water in the water jacket WJ.

[Impeller configuration]
Next, the impeller 100 according to the present embodiment will be described with reference to FIGS. 4 to 9 additionally. Hereinafter, for convenience of explanation, the upper side of the axial direction (center axis direction) is defined as “one end side” and the lower side of the axial direction (center axis direction) with reference to the arrangement posture of the impeller 100 illustrated in FIG. The side is also referred to as “the other end side”. 4 to 9, the cross-sectional hatching is omitted for easy understanding of the drawings. In each figure, the rotation direction of the impeller 100 is appropriately indicated by an arrow “X”.

4 and 5, the impeller 100 is a so-called closed structure mainly composed of a cover 110 in which a plurality of blades 130 are integrally formed and a shroud 150 joined to the cover 110. Impeller. The impeller 100 rotates in synchronization with the drive shaft 30 described above, sucks cooling water from a suction port 123 formed in the cover 110, and discharges the cooling water from a discharge port 139 which is a space between the blades 130. To do.

As shown in FIGS. 6 and 7, the cover 110 is formed as an integrally molded product made of resin (preferably made of PPS resin), and a plurality of blades 130 are integrally provided on the cover main body 120. It is configured.

The cover main body 120 is formed in a truncated cone shape (substantially umbrella shape) whose diameter increases from one end side to the other end side, and has a circular hole shape for introducing cooling water from the suction port 11 at the center thereof. The suction port 123 is penetrated in the axial direction. The surface 121 of the cover main body 120 is disposed to face the inner surface of the pump base 10. A plurality of blades (seven blades in this embodiment) 130 are provided on the back surface 122 of the cover body 120 at equal intervals in the circumferential direction. In addition, by making the cover main body 120 into a taper shape (substantially umbrella shape), the flow of cooling water can be made smooth along the back surface 122 of this cover main body 120.

Note that the peripheral edge 124 of the suction port 123 in the cover main body 120 is formed shorter in the axial direction than in the prior art, as shown in FIG. And the end surface (left surface in FIG. 2) of the peripheral edge 124 and the end surface (right surface in FIG. 2) of the pipe 14 of the suction port 11 are opposed to each other with a very small gap. As a result, when the closed impeller is employed, even if the cover body 120 protrudes in the axial direction (leftward in FIG. 2) by the thickness of the cover main body 120, the existing pump casing is not increased without increasing the volume of the pump chamber 2. The impeller 100 can be accommodated in the pump chamber 2 as it is, and the backflow of the cooling water from the gap between the cover main body 120 and the pump base 10 can be reduced.

Each blade 130 is formed in a plate shape curved along a center line in which a convex curve and a concave curve are continuously connected. The plurality of blades 130 are arranged radially around the axis, and the circumferential interval between adjacent blades 130 is directed from the radially inner side to the radially outer side (that is, toward the cooling water discharge direction). E) is formed so as to gradually increase. The blades 130 are inclined so as to decrease in height from the radially inner side to the radially outer side, corresponding to the tapered shape of the cover body 120. As a result, the cross-sectional area of the radially inner (suction side) opening between the blades 130 adjacent to each other and the cross-sectional area of the radially outer (discharge side) opening are set to be approximately equal to each other. Can be made uniform.

The blade 130 has a tip 131 that faces the shroud 150, a rear outer surface 132 formed on the rear side in the rotational direction, and a front outer surface 133 formed on the front side in the rotational direction. The rear side outer surface 132 and the front side outer surface 133 are each formed as an inclined surface having a gradient of about 2 degrees in a direction approaching each other from one end side to the other end side in the axial direction. Therefore, the blades 130 are slightly tapered from one end side to the other end side in a cross-sectional view. Further, the tip 131 side of the blade 130 is formed so as to be receivable in a long groove 170 recessed in the shroud 150. And the corner | angular part between the front-end | tip part 131 of this blade | wing 130 and the front side outer surface 133 is comprised as a site | part (welding contact part 135) welded with the shroud 150. FIG.

As shown in FIGS. 8 and 9, the shroud 150 includes a shroud main body 160 formed as an integrally molded product made of resin (preferably made of PPS resin), and a metal bush insert-molded in the shroud main body 160. 180.

The shroud main body 160 includes a cylindrical boss portion 161 and a disk portion 165 formed to have substantially the same diameter as the cover 110. A hollow bush 180 is embedded in the center of the boss portion 161 and is connected to the drive shaft 30 so as to be integrally rotatable. A plurality of blades 130 are welded and joined to the surface 166 side of the disk portion 165, and the back surface 167 side of the disk portion 165 becomes a contact surface with the ultrasonic horn H during welding (see FIG. 10). The disk portion 165 is formed with three circular hole-shaped balance holes 168 penetrating the front and back.

In the surface 166 of the disk portion 165, a long groove 170 extending in the radial direction from the vicinity of the outer peripheral surface of the cylindrical portion 161 is recessed at a position aligned with each blade 130. The long groove 170 is open to one end side facing the cover 110 and is formed so as to receive the tip 131 side of the blade 130.

The long groove 170 has a groove bottom 171, a rear inner surface 172 formed on the rear side in the rotation direction, and a front inner surface 173 formed on the front side in the rotation direction.

The rear side inner surface 172 is formed as an inclined surface having a gradient of about 2 degrees in a direction away from the front side inner surface 173 from the other end side in the axial direction toward one end side.

The front-side inner surface 173 has a first front-side inner surface 174, a second front-side inner surface 175, and a third front-side inner surface 176 in order from the bottom surface side. The first front inner surface 174 faces the rear inner surface 172 with a first groove width therebetween. The first front side inner surface 174 is formed as an inclined surface having a gradient of about 2 degrees in a direction away from the front end side inner surface from the other end side in the axial direction toward the one end side. The third front side inner surface 176 is opposed to the rear side inner surface 172 with a second groove width larger than the first groove width. The second front-side inner surface 175 connects the first front-side inner surface 174 and the third front-side inner surface 176, and extends approximately away from the rear-side inner surface 172 from the other end side in the axial direction toward the one end side. It is formed as an inclined surface having a 45 degree gradient. The rear inner surface 172 becomes a part that can come into contact with the rear outer surface 132 of the blade 130, and the second front inner surface 175 becomes a part (welding receiving part 177) welded to the welding contact part 135 of the blade 130.

In addition, excess molten resin generated at the time of welding between the welding contact portion 135 and the welding receiving portion 177 is accumulated in the vicinity of the groove bottom portion 171 and the third front side inner surface 176 in the long groove 170. That is, the gap between the groove bottom 171 of the long groove 170 and the tip 131 of the blade 130, the gap between the third front inner surface 176 of the long groove 170 and the front outer surface 133 of the blade 130, etc. function as a resin reservoir during welding. To do.

In this embodiment, the tip 131 of the blade 130 and the long groove 170 of the shroud 150 are welded only on the front side in the rotational direction. However, the tip 131 of the blade 130 and the long groove 170 of the shroud 150 are welded forward in the rotational direction. A method of welding on both the side and the rear side is also conceivable. However, in such a case, if the timing of melting is not matched between the front side and the rear side in the rotation direction, there is a possibility that a large residual stress may be generated. Therefore, welding is performed only on one side (front side or rear side) in the rotation direction. Is preferred.

[Impeller manufacturing method]
Next, a method for manufacturing the impeller 100 according to the present embodiment will be described with reference to FIGS. 10 and 11 additionally. In FIG. 11, in order to facilitate understanding of the welding process, the positional relationship between the welding contact portion 135 and the welding receiving portion 177 is illustrated in a vertically inverted state.

In this embodiment, the impeller 100 is manufactured by joining a resin cover 110 and a shroud 150 together by ultrasonic welding.

In order to manufacture such an impeller 100, first, the cover 110 and the shroud 150 are individually molded. The cover 110 is injection-molded using a predetermined mold made of synthetic resin. Similarly, the shroud 150 is injection-molded using a predetermined mold made of synthetic resin. The shroud 150 is insert-molded with a bush 180 as a metal insert part.

Subsequently, the cover 110 and the shroud 150 are attached to the jig 900. The jig 900 has a substantially cylindrical shape having an opening on the upper side, and is formed so that the cover 110 and the shroud 150 can be attached to the opening 901. In the opening 901 of the jig 900, the cover 110 and the shroud 150 are mounted in this order, the cover 110 is disposed on the lower side, and the shroud 150 is disposed on the upper side. At this time, by positioning the cover 110 and the shroud 150 in the circumferential direction, the tip 131 of the blade 130 is received in the long groove 170 of the shroud 150, and the cover 110 and the shroud 150 are moved in the opening 901 of the jig 900. It will be in the state polymerized up and down. A shaft-shaped guide pin 910 is erected in a vertical posture at the center of the jig 900. Then, the bush 180 of the shroud 150 is fitted into the guide pin 910 so that the shroud 150 is disposed concentrically with the jig 900. Further, the outermost peripheral surface of the cover 110 and the shroud 150 and the inner peripheral surface of the jig 900 have a so-called stamping structure, whereby the alignment of the cover 100 and the shroud 150 is adjusted. The jig 900 receives the surface 121 side (the lower side in FIG. 10) of the cover 110 by surface contact. Thus, in a state where the cover 110 and the shroud 150 are mounted on the jig 900, the axial center of the cover 110 and the axial center of the shroud 150 are aligned and coincide with each other, and the axial direction is directed vertically.

Subsequently, the ultrasonic horn H of the welding machine is brought into contact with the back surface 167 of the shroud 150, and the cover 110 and the shroud are applied to the cover 110 and the shroud 150 in the up and down directions simultaneously with ultrasonic vibration. 150 is ultrasonically welded. Specifically, the front end 131 side of the blade 130 is received in the long groove 170 of the shroud 150, and the welding contact portion (corner portion) 135 of the blade 130 is brought into contact with the welding receiving portion (inclined surface) 177 of the long groove 170. In this state, ultrasonic vibration is applied in the same direction while pressing downward.

At this time, when the shroud 150 is pressed downward by the ultrasonic horn H, the rear outer surface 132 of the blade 130 comes into contact (sliding contact) with the rear inner surface 172 of the long groove 170, so that the rear inner surface 172 and the rear side The outer surface 132 acts as a guide surface when the welding contact portion 135 is pushed into the welding receiving portion 177. Further, when pressurizing the welding contact portion 135 to the welding receiving portion 177, the welding contact portion 135 receives the action of the inclined surface of the welding receiving portion 177, and the entire blade 130 escapes to the rear side inner surface 172 side in the long groove 170. Even if it tries to move, the rear outer surface 132 and the rear inner surface 172 are in contact with each other, so that the welding contact portion 135 and the welding receiving portion 177 can be kept in contact with each other at an appropriate position. The ultrasonic vibration generated by the ultrasonic horn H propagates intensively to the contact portion between the welding contact portion (corner portion) 133 of the blade 130 and the welding receiving portion (inclined surface) 177 of the long groove 170, and at the contact portion between the two. When the frictional heat is generated, the contact portion is melted and the cover 110 and the shroud 150 are welded.

Here, since the shear joint is formed by the welding contact portion 135 and the welding receiving portion 177, it is possible to secure a wide mutual welding area and improve the bonding strength (mechanical strength) between the cover 110 and the shroud 150. Can do. Further, in the share joint, since the actually melted surfaces of the welding contact portion 135 and the welding receiving portion 177 are in contact with each other, it is difficult to entrain air at the time of welding, and the occurrence of defects such as voids can be prevented. . Furthermore, since the rear side outer surface 132 and the rear side inner surface 172 are joined in contact, the rear side inner surface 172 functions as a wall that receives a load applied to the blade 130 during the operation of the water pump 1.

As described above, according to the impeller 100 according to the present embodiment, the shroud 150 is in a state in which the front end portion 131 of the blade 130 (particularly, the ridge line at the corner of the welding contact portion 135) and the back surface of the shroud 150 are in a parallel positional relationship. The cover 110 and the shroud 150 are pressurized and vibrated by using the back surface side of the cover as a contact surface with the ultrasonic horn H, and the welding contact portion 135 of the cover 110 and the welding receiving portion 177 of the shroud 150 are welded. As a result, the pressure surface of the ultrasonic horn H and the welded portion of the blade 130 and the shroud 150 are parallel to each other, and as a result, vibration transmission loss (energy loss at the time of vibration transmission) is reduced. Stable quality can be realized. Therefore, even if the impeller (closed impeller) 100 is manufactured by welding and joining the cover 110 and the shroud 150, the joint strength can be increased and the pump performance can be improved without increasing the cost by a simple structure. In addition, there is an effect that a complicated blade shape and development to a large capacity pump can be realized.

Further, in the impeller 100 according to the present embodiment, the welding portion between the welding contact portion 135 and the welding receiving portion 177 is formed as a shear joint, while the rear side inner surface 172 pushes the welding contact portion 135 into the welding receiving portion 177. The rear outer surface 132 and the rear inner surface act as a guide surface when the welding contact portion 135 receives the action of the inclined surface of the welding receiving portion 177 and tries to move away in the separation direction (rear inner surface 172 side). Since it is in contact with 172, the escape movement of the welding contact portion 135 in the separation direction is restricted. Therefore, on the rear side in the rotation direction of the blades 130, the positioning accuracy of the welding contact portion 135 and the welding receiving portion 177 at the time of welding is improved by bringing the rear outer surface 132 and the rear inner surface 172 into sliding contact. In addition, on the front side in the rotation direction of the blade 130, the welded portion between the weld contact portion 135 and the weld receiving portion 177 is formed as a shear joint, so that a large welding area can be secured, so the cover 110 and the shroud 150 can be secured. It is possible to further increase the bonding strength and to prevent the occurrence of defects such as voids by making it difficult to entrain air during welding.

It should be noted that the present invention is not limited to the above-described embodiment, and can be improved as appropriate without departing from the gist of the present invention.

In the above-described embodiment, the description has been given by exemplifying the char joint. However, the present invention is not limited to this configuration. For example, an ED joint (energy director joint) may be applied. As an example of the ED joint, a triangular protrusion (corner) is formed on the tip of the blade as a welding contact portion, and a flat surface is formed in the groove portion as a welding receiving portion, so that both may be welded together. Good. Conversely, the tip of the blade may be formed on a flat surface as the welding contact portion, and a triangular protrusion (corner portion) may be formed in the groove portion as the welding receiving portion, and both may be welded together.

In the above-described embodiment, the engine-driven water pump is described as an example. However, the present invention is not limited to this configuration, and may be applied to an electric water pump. Moreover, it is not limited to a water pump, You may apply to other fluid pumps, such as a fuel pump and an oil pump.

1 Water pump (fluid pump)
2 Pump chamber 10 Pump base 20 Pump body 100 Impeller 110 Cover (impeller cover member)
120 Cover body 130 Blade 131 Tip portion 132 Rear outer surface (first outer surface)
133 Front side outer surface (second outer surface)
135 Welding section 150 Shroud (impeller body member)
170 Long groove (groove)
172 Rear side inner surface (first inner surface)
173 Front side inner surface (second inner surface)
177 Welding receiving part 180 Bush

Claims

It has a disk-shaped impeller body member that is driven to rotate about the central axis, a frustoconical cover body with a fluid suction port formed at the center, and a plurality of blades provided around the central axis of the cover body. An impeller cover member, and an impeller of a fluid pump in which the impeller body member and the impeller cover member are disposed to face each other in a central axis direction,
The cover body has an inclined portion that is inclined radially outward toward the impeller body member in the central axis direction, and the plurality of blades are disposed on a side of the inclined portion that faces the impeller body member. And
The blade has a welding contact portion on a tip portion facing the impeller body member in the central axis direction,
The impeller body member is recessedly provided at one end face facing the impeller cover member, the other end face disposed on the opposite side of the one end face in the central axis direction, and a position aligned with the blades on the one end face. A groove portion that receives the tip portion of the blade, and a welding receiving portion that is formed in the groove portion and can contact the welding contact portion;
By welding the welding contact portion and the welding receiving portion in a central axis direction in a state where the other end surface of the impeller body member and the tip end portion of the impeller cover member are in a parallel positional relationship, the impeller An impeller for a fluid pump, wherein a main body member and the impeller cover member are joined.
The blade has the tip portion, a first outer surface connected to the tip portion on the rear side in the rotation direction, and a second outer surface connected to the tip portion on the front side in the rotation direction,
The groove portion includes a groove bottom portion facing the tip portion in the central axis direction, a first inner surface connected to the groove bottom portion on the rear side in the rotation direction and in contact with the first outer surface, and the groove bottom portion on the front side in the rotation direction. A second inner surface connected to the first inner surface and opposed to the first inner surface,
The welding contact portion is formed at a corner portion between the tip portion and the second outer surface of the blade, and the welding receiving portion serving as an inclined surface is formed on the second inner surface of the groove portion. The impeller of the fluid pump according to claim 1.